Southern Catalpa (Catalpa bignonioides)
- Southern Catalpas are very adaptable tough trees, having naturalized in many parts of the south. Popular in older gardens, they reach 20 to 40 feet tall and have a moderately-long life (60 years or so).
- This is a very adaptable tree because it tolerates wet and dry sites and will easily adapt to full sun or partial shade, although a sunny exposure and a well-drained, moist, rich soil is preferred for best growth of Catalpa.
- Growth is rapid at first but slows down with age as the crown begins to round out and the tree increases in spread. The main ornamental feature is panicles of white with yellow and purple markings produced in spring and early summer. Flowers make somewhat of a slimy mess for a short period when they drop on a sidewalk but are not a problem falling into shrubs, groundcovers, or turf. The fruit is a long pod (up to two feet long) resembling a string bean that can be a slight litter problem to some, but it is quite interesting.
- Catalpas are planted to attract Catalpa worms, a large caterpillar prized for fish bait because the skin is very tough and the caterpillar is juicy. The caterpillar (the larva of the Catalpa sphinx moth) can eat large quantities of leaves and defoliate the tree once or twice a year but there appear to be no adverse consequences to the tree.
- During hot, dry seasons the leaves may turn yellow and brown due to scorch, but the tree lives. Little can be done other than watering.